using System;
using System.ComponentModel;
using System.Drawing;
using System.Globalization;
using System.Text;
using GreenshotPlugin.Effects;

namespace Greenshot.Core
{
	public class EffectConverter : TypeConverter {
		// Fix to prevent BUG-1753
		private readonly NumberFormatInfo _numberFormatInfo = new NumberFormatInfo();

		public EffectConverter()
		{
			_numberFormatInfo.NumberDecimalSeparator = ".";
			_numberFormatInfo.NumberGroupSeparator = ",";
		}

		public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType) {
			if (sourceType == typeof(string)) {
				return true;
			}
			return base.CanConvertFrom(context, sourceType);
		}

		public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType) {
			if (destinationType == typeof(string)) {
				return true;
			}
			if (destinationType == typeof(DropShadowEffect)) {
				return true;
			}
			if (destinationType == typeof(TornEdgeEffect)) {
				return true;
			}
			return base.CanConvertTo(context, destinationType);
		}

		public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType) {
			// to string
			if (destinationType == typeof(string)) {
				StringBuilder sb = new StringBuilder();
				if (value.GetType() == typeof(DropShadowEffect)) {
					DropShadowEffect effect = value as DropShadowEffect;
					RetrieveDropShadowEffectValues(effect, sb);
					return sb.ToString();
				}
				if (value.GetType() == typeof(TornEdgeEffect)) {
					TornEdgeEffect effect = value as TornEdgeEffect;
					RetrieveDropShadowEffectValues(effect, sb);
					sb.Append("|");
					RetrieveTornEdgeEffectValues(effect, sb);
					return sb.ToString();
				}
			}
			// from string
			if (value is string) {
				string settings = value as string;
				if (destinationType == typeof(DropShadowEffect)) {
					DropShadowEffect effect = new DropShadowEffect();
					ApplyDropShadowEffectValues(settings, effect);
					return effect;
				}
				if (destinationType == typeof(TornEdgeEffect)) {
					TornEdgeEffect effect = new TornEdgeEffect();
					ApplyDropShadowEffectValues(settings, effect);
					ApplyTornEdgeEffectValues(settings, effect);
					return effect;
				}
			}
			return base.ConvertTo(context, culture, value, destinationType);
		}

		public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value) {
            if (value is string settings) {
				if (settings.Contains("ToothHeight")) {
					return ConvertTo(context, culture, settings, typeof(TornEdgeEffect));
				}
				return ConvertTo(context, culture, settings, typeof(DropShadowEffect));
			}
			return base.ConvertFrom(context, culture, value);
		}

		private void ApplyDropShadowEffectValues(string valuesString, DropShadowEffect effect) {
			string[] values = valuesString.Split('|');
			foreach(string nameValuePair in values) {
				string[] pair = nameValuePair.Split(':');
				switch (pair[0]) {
					case "Darkness" :
                        // Fix to prevent BUG-1753
						if (pair[1] != null && float.TryParse(pair[1], NumberStyles.Float, _numberFormatInfo, out var darkness)) {
							if (darkness <= 1.0) {
								effect.Darkness = darkness;
							}
						}
						break;
					case "ShadowSize":
                        if (int.TryParse(pair[1], out var shadowSize)) {
							effect.ShadowSize = shadowSize;
						}
						break;
					case "ShadowOffset":
						Point shadowOffset = new Point();
                        string[] coordinates = pair[1].Split(',');
						if (int.TryParse(coordinates[0], out var shadowOffsetX)) {
							shadowOffset.X = shadowOffsetX;
						}
						if (int.TryParse(coordinates[1], out var shadowOffsetY)) {
							shadowOffset.Y = shadowOffsetY;
						}
						effect.ShadowOffset = shadowOffset;
						break;
				}
			}
		}

		private void ApplyTornEdgeEffectValues(string valuesString, TornEdgeEffect effect) {
			string[] values = valuesString.Split('|');
			foreach (string nameValuePair in values) {
				string[] pair = nameValuePair.Split(':');
				switch (pair[0]) {
					case "GenerateShadow":
                        if (bool.TryParse(pair[1], out var generateShadow)) {
							effect.GenerateShadow = generateShadow;
						}
						break;
					case "ToothHeight":
                        if (int.TryParse(pair[1], out var toothHeight)) {
							effect.ToothHeight = toothHeight;
						}
						break;
					case "HorizontalToothRange":
                        if (int.TryParse(pair[1], out var horizontalToothRange)) {
							effect.HorizontalToothRange = horizontalToothRange;
						}
						break;
					case "VerticalToothRange":
                        if (int.TryParse(pair[1], out var verticalToothRange)) {
							effect.VerticalToothRange = verticalToothRange;
						}
						break;
					case "Edges":
						string[] edges = pair[1].Split(',');
                        if (bool.TryParse(edges[0], out var edge)) {
							effect.Edges[0] = edge;
						}
						if (bool.TryParse(edges[1], out edge)) {
							effect.Edges[1] = edge;
						}
						if (bool.TryParse(edges[2], out edge)) {
							effect.Edges[2] = edge;
						}
						if (bool.TryParse(edges[3], out edge)) {
							effect.Edges[3] = edge;
						}
						break;
				}
			}
		}

		private void RetrieveDropShadowEffectValues(DropShadowEffect effect, StringBuilder sb) {
			// Fix to prevent BUG-1753 is to use the numberFormatInfo
			sb.AppendFormat("Darkness:{0}|ShadowSize:{1}|ShadowOffset:{2},{3}", effect.Darkness.ToString("F2", _numberFormatInfo), effect.ShadowSize, effect.ShadowOffset.X, effect.ShadowOffset.Y);
		}
		private void RetrieveTornEdgeEffectValues(TornEdgeEffect effect, StringBuilder sb) {
			sb.AppendFormat("GenerateShadow:{0}|ToothHeight:{1}|HorizontalToothRange:{2}|VerticalToothRange:{3}|Edges:{4},{5},{6},{7}", effect.GenerateShadow, effect.ToothHeight, effect.HorizontalToothRange, effect.VerticalToothRange, effect.Edges[0], effect.Edges[1], effect.Edges[2], effect.Edges[3]);
		}
	}
}